[Mp4-tech] Question About H.264/AVC ---- POC

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Forwarding bounced email.
Sandro, thanks for the answer, but please subscribe to the mp4-tech list
with your sending address. Thanks.
Rob 
> -----Original Message-----
> From: Sandro Moiron [mailto:sandromoiron gmail.com] 
> Sent: Wednesday, 21 December 2023 17:12
> To: mp4-tech lists.mpegif.org
> Cc: Ming Yang
> Subject: Re: [Mp4-tech] Question About H.264/AVC ---- POC
> 
> Hi,
> 
> First of all I recommend you to take a look at H.264 doc, 
> take it from here or 
> from ITU:
> http://www.student.estg.ipleiria.pt/~ee09176/H.264%2003_05%20A
dvanced%20video%20coding%20for%20generic%20audiovisual%20-%20d0181c953763b20
b4634391f1fa65fd9-1.pdf?sessionid=ee09176*-session-0.842751042794049¤t
dir=%2Fpublic_html&action=download&selitems=H.264%2003_05%20Advanced%20video
%20coding%20for%20generic%20audiovisual%20-%20d0181c953763b20b4634391f1fa65f
d9-1.pdf
When you talk about the frame # order...do you have something like this on
the 
decoder ?
0000(IDR)  150576   28  36.243  38.136  39.855      8812       0    FRM    1
0002(P)     46464   28  34.968  37.594  39.451     10044    1331    FRM    1
0001(B)      9232   30  33.428  37.603  39.418     12323    4016    FRM    0
0004(P)     41240   28  35.021  37.542  39.626     11358    2763    FRM    1
0003(B)      9664   30  33.401  37.412  39.253     15186    6023    FRM    0
0006(P)     41616   28  35.088  37.608  39.665     14335    4714    FRM    1
0005(B)      7864   30  33.453  37.504  39.538     15023    6545    FRM    0
0008(P)     40720   28  35.056  37.515  39.687     13952    5356    FRM    1
0007(B)      7608   30  33.479  37.492  39.710     15847    7751    FRM    0
0010(P)     40960   28  35.094  37.366  39.569     15518    6646    FRM    1
0009(B)      9896   30  33.412  37.322  39.375     16107    7828    FRM    0
0012(P)     40496   28  35.063  37.390  39.643     15296    6678    FRM    1
0011(B)      7416   30  33.447  37.284  39.584     15842    7791    FRM    0
0014(P)     44256   28  35.028  37.154  39.509     15426    6612    FRM    1
0013(B)      9440   30  33.519  37.175  39.563     16191    7818    FRM    0
0016(P)     48168   28  35.006  37.115  39.466     15383    6673    FRM    1
0015(B)     12120   30  33.453  36.984  39.162     16095    7889    FRM    0
0018(P)     48664   28  34.993  37.120  39.390     15853    6901    FRM    1
...(tempete encoding)
the reason for that hop is because the encoder has to encode the P frames 
before the B frames in order to encode it bidirectionaly.
Sandro
On Tuesday 20 December 2023 22:00, Ming Yang wrote:
> Dear all:
>
> I have some questions about H.264/AVC JM10.1:
>
> (1) What does POC mean in the decoder output?
>
> (2) What does POC Gap mean?
>
> (3) What does IPP /IbP/IpP mean?
>
> (4) Howcome the output frame #s are always:
>       0000
>       0002
>       0004
>       0006
>       .........
> they are not consecutive numbers no matter how I set IntraPeriod,
> FrameSkip, and NumberBFrames. Even if the original video sequence is
> encoded as all I-frames, the output is still like this.
>
> Can anybody explain this to me? Thank you very much.
>
> Ming